Asthma Management Handbook

Investigating new asthma-like symptoms in older adults

Recommendations

Consider the possibility of adult-onset asthma in adults of any age with dyspnoea, wheeze or cough, even older people without a history of asthma.

How this recommendation was developed

Consensus

Based on clinical experience and expert opinion (informed by evidence, where available).

When taking a history, ask about:

  • lifetime smoking history (including exposure to environmental tobacco smoke)
  • comorbid conditions
  • new medicines or a change in the regimen
  • occupational exposure to allergens or irritants
  • new hobbies that may expose the person to new allergens or irritants.
How this recommendation was developed

Consensus

Based on clinical experience and expert opinion (informed by evidence, where available).

When investigating new respiratory symptoms that suggest asthma, perform or arrange spirometry before and 15 minutes after bronchodilator, as for younger adults.

Note: If reliable equipment and appropriately trained staff are available, spirometry can be performed in primary care. If not, refer to an appropriate provider such as an accredited respiratory function laboratory.

How this recommendation was developed

Consensus

Based on clinical experience and expert opinion (informed by evidence, where available), with particular reference to the following source(s):

  • Reed, 20101

Before doing spirometry, assess comorbidities and check if the person has any contraindications to spirometry. Advise patients to empty their bladder before spirometry.

How this recommendation was developed

Consensus

Based on clinical experience and expert opinion (informed by evidence, where available).

If FEV1 improves after administering short-acting beta2 agonist but the response does not meet criteria for acute response to bronchodilator, repeat spirometry 6–8 weeks after a treatment trial of an inhaled corticosteroid. Compare pre-bronchodilator FEV1 with the pre-bronchodilator FEV1 reading from the previous visit.

How this recommendation was developed

Consensus

Based on clinical experience and expert opinion (informed by evidence, where available).

If spirometry before and after bronchodilator demonstrates expiratory airflow limitation that is not completely reversible, consider the possibility of COPD as an alternative diagnosis or of asthma–COPD overlap, even if the person has never smoked.

Note: people with longstanding asthma can develop fixed airflow limitation that resembles COPD.

How this recommendation was developed

Consensus

Based on clinical experience and expert opinion (informed by evidence, where available), with particular reference to the following source(s):

  • Gibson et al. 20102
  • Gibson and Simpson, 20093
  • McDonald et al. 20124
  • Abramson et al. 20125
  • Reed, 20101

More information

Asthma prevalence in older adults

An estimated 7–15% of Australians aged 65 years or over have asthma, similar to asthma prevalence in the general adult population.6 According to the latest available Australian population survey data (2011–2012),7 self-reported current asthma rates among those aged 65–74 years are 9% for men and 13% for women, and among those aged 75 years and over are 8% for men and 13% for women.

New cases of adult-onset asthma can occur at any age.2 Asthma is under-diagnosed and commonly misdiagnosed in older people.2, 6, 89, 10 The diagnosis is unrecognised in an estimated 50% of people with asthma aged over 75 years.2

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Effects of ageing on the lungs

Lung function peaks at age 20–25 years, then progressively falls throughout life.2 Age-related decrease in lung function is greater in men than in women.1

Ageing is associated with increased work of breathing, weakening of respiratory muscles, and inflammation of the airways.2

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Asthma presentation in older adults

Asthma presents with the same clinical features in older adults as in younger adults.6 However, older patients may under-report symptoms and attribute breathlessness to age or other comorbidities.2, 6

Wheeze and whistling in the chest are common (particularly in those aged over 75 years) and can be due to asthma, COPD, cardiac failure, acute bronchitis, bronchiectasis, cancer, or pulmonary embolism.2 Wheezing can also occur in obese people who do not have asthma. Approximately one-third of people over 75 years old experience breathlessness.2

As with any patient, a careful history is necessary to identify symptoms and triggers. Physical examination should include examination of upper airway and chest auscultation, and alternative causes of respiratory symptoms should be considered and investigated as indicated.

Ask about new hobbies that may expose the person to new airborne allergens or irritants (e.g. woodworking, bird-keeping or home renovation projects). Asthma that begins in late adult life is rarely immunoglobulin E (IgE)-mediated.1 However, allergic sensitisation is still common enough among older patients with respiratory symptoms to warrant allergy tests in the investigation of asthma-like symptoms11 when allergic triggers are suspected (e.g. if history suggests that symptoms worsen seasonally or in certain places, or if control not achieved despite adherence to appropriate treatment and correct inhaler technique).

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Lung function testing in older adults

More than 90% of patients with obstructive airway disease aged 65 years and over can perform an acceptable spirometry test (when staff are appropriately trained and rigorous quality control protocols are followed).2, 12, 13

Contraindications to spirometry include conditions in which increased blood pressure, intraocular pressure, intra-abdominal or intrathoracic pressure may be dangerous, such as unstable cardiovascular disease, recent myocardial infarction, recent pulmonary embolus, aneurysm, and recent cataract surgery.14 Advise patients to empty their bladder before spirometry, because the effort required may cause leaking for those with urinary incontinence.

FEV1/FVC ratio decreases with normal ageing. Reference values for forced expiratory volume in one second (FEV1) and ratio of FEV1 to forced vital capacity (FEV1/FVC) applicable to people aged up to 95 years have been developed.15 Reference values for older people are incorporated into newer spirometers. Airflow limitation should not be diagnosed based solely on the shape of the flow–volume loop.

Some degree of concavity in the expiration flow–volume curve (typical of airflow limitation) occurs as people age, even without asthma.

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Definition of variable expiratory airflow limitation

Most of the tests for variable expiratory airflow limitation are based on showing variability in FEV1. While reduced FEV1 may be seen with many other lung diseases (or due to poor spirometric technique), a reduced ratio of FEV1 to FVC indicates airflow limitation.16 Normal FEV1/FVC values derived from population studies vary,1715 but are usually greater than:17

  • 0.85 in people aged up to 19 years
  • 0.80 in people aged 20–39 years
  • 0.75 in people aged 40–59 years
  • 0.70 in people aged 60–80 years.

In children, it is less useful to define expiratory airflow limitation according to a specific cut-off for FEV1/FVC ratio, because normal values in children change considerably with age.15

Some spirometers provide predicted normal values specific to age group. If these are available, a FEV1/FVC ratio less than the lower limit of normal (i.e. less than the 5th percentile of normal population) indicates airflow limitation.

Variable expiratory airflow limitation (beyond the range seen in healthy populations) can be documented if any of the following are recorded:

  • a clinically important increase in FEV1 (change in FEV1 of at least 200 mL and 12% from baseline for adults, or at least 12% from baseline for children) 10–15 minutes after administration of bronchodilator
  • clinically important variation in lung function (at least 20% change in FEV1) when measured repeatedly over time (e.g. spirometry on separate visits)
  • a clinically important reduction in lung function (decrease in FEV1 of at least 200 mL and 12% from baseline on spirometry, or decrease in peak expiratory flow rate by at least 20%) after exercise (formal laboratory-based exercise challenge testing uses different criteria for exercise-induced bronchoconstriction)
  • a clinically important increase in lung function (at least 200 mL and 12% from baseline) after a trial of 4 or more weeks of treatment with an inhaled corticosteroid
  • clinically important variation in peak expiratory flow (diurnal variability of more than 10%)
  • a clinically important reduction in lung function (15–20%, depending on the test) during a test for airway hyperresponsiveness (exercise challenge test or bronchial provocation test) measured by a respiratory function laboratory.

Notes

Patients referred to a respiratory function laboratory may be asked not to take certain medicines within a few hours to days before a spirometry visit.

A clinically important increase or decrease in lung function is defined as a change in FEV1 of at least 200 mL and 12% from baseline for adults, or at least 12% from baseline for children, or a change in peak expiratory flow rate of at least 20% on the same meter.1816 A clinically important increase in FVC after administering bronchodilator may also indicate reversible airflow limitation, but FVC is a less reliable measure in primary care because FVC may vary due to factors such as variation in inspiratory volume or expiratory time.

The finding of ‘normal’ lung function during symptoms reduces the probability that a patient has asthma, but a clinically important improvement in response to bronchodilator or inhaled corticosteroid can occur in patients whose baseline value is within the predicted normal range.

The greater the variation in lung function, the more certain is the diagnosis of asthma. However, people with longstanding asthma may develop fixed airflow limitation.

Reversibility in airflow limitation may not be detected if the person is already taking a long-acting beta2 agonist or inhaled corticosteroid.

Airflow limitation can be transient and does not necessarily mean that the person has asthma (e.g. when recorded during a severe acute infection of the respiratory tract). Ideally, airflow limitation should be confirmed when the patient does not have a respiratory tract infection. Reduction in lung function during a respiratory tract infection with improvement in lung function after its resolution, commonly occurs in people with asthma, but can also be seen in patients with COPD or in healthy people without either asthma or COPD.19,20

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Asthma–COPD overlap

Distinguishing between typical allergic asthma (childhood-onset allergic asthma) and typical COPD (emphysema in a heavy smoker) is straightforward.21 However, it can be difficult to distinguish COPD from asthma in adults who have features of both conditions.22, 23These people are described as having asthma–COPD overlap.22, 21, 3

Asthma–COPD overlap is not a single, well-defined disease entity, but includes a range of airway disease phenotypes with different causal mechanisms.22, 24 Features of both asthma and COPD have been described in:3, 4, 1, 25

  • people with current asthma (allergic or non-allergic) who have had significant exposure to tobacco smoke
  • people with longstanding asthma or late-onset asthma who have become persistently short of breath over time
  • people significant smoking history and symptoms consistent with COPD who also have a history of childhood asthma
  • people who present in middle age or later with shortness of breath, with a history of childhood asthma but no or few symptoms in between, and little smoking history.

Figure. Development of asthma, COPD and asthma–COPD overlap Opens in a new window Please view and print this figure separately: http://www.asthmahandbook.org.au/figure/show/108

People with asthma–COPD overlap often have poor disease outcomes, including:22, 2627, 28, 29

  • high need for healthcare services
  • worse quality of life, more wheezing, dyspnoea, cough and sputum production, and more frequent and severe respiratory exacerbations and hospitalisations, than people with COPD or asthma alone
  • worse lung function demonstrated by spirometry than those with COPD alone, despite lower average exposure to tobacco smoke.

Features of asthma, COPD and asthma–COPD overlap

If several features of both asthma and COPD are present and neither condition is strongly favoured, respiratory disease should be managed according to recommendations for asthma–COPD overlap.

Table. Features that, when present, favour asthma or COPD

Clinical feature (if measured/relevant)

Asthma more likely

COPD more likely

Age of onset

Before 20 After 40

Pattern of symptoms

Variation in respiratory symptoms:

  • changes over minutes, hours or days
  • worse at night or early morning
  • triggered by exercise, emotions, airborne pollutants or allergens

Persistence of respiratory symptoms despite treatment

Symptoms every day, including exertional dyspnoea

History of chronic cough and sputum unrelated to specific triggers, before onset of dyspnoea

Lung function

Expiratory airflow limitation* is variable#

Lung function normal between symptoms

Expiratory airflow limitation* is persistent

Lung function abnormal between symptoms

History

Previous diagnosis of asthma

Family history of asthma and allergies§ (allergic rhinitis or eczema)

Previous diagnosis of COPD, chronic bronchitis or emphysema

Heavy exposure to tobacco smoke or biomass fuels

Long-term disease trajectory

Seasonal or yearly variation in symptoms

Improvements (spontaneously or in response to medication) last for weeks

Slowly worsens over years

Relief in response to medication is limited and short term

Chest X-ray

Normal Severe hyperinflation

Features that, when present, increase the probability of either typical asthma or typical COPD. None of these features is essential to make the diagnosis of asthma or COPD, with the exception of persistent airflow limitation for making the diagnosis of COPD.

* Expiratory airflow limitation: indicated by a reduced ratio of forced expiratory volume in one second (FEV1) to forced vital capacity (FVC) on spirometry (FEV1/FVC less than the lower limit of normal (i.e. less than the 5th percentile of normal population). Typical FEV1/FVC values derived from population studies are > 0.75 in people aged 40–59 years and > 0.70 in people aged 60–80 years.

# Variable expiratory airflow limitation: variation beyond the range seen in healthy populations. It is indicated in adults by any of the following:

  • a clinically important increase in FEV1 (change in FEV1 of at least 200 mL and 12% from baseline) 10–15 minutes after administration of bronchodilator
  • clinically important variation in lung function (at least 20% change in FEV1) when measured repeatedly over time (e.g. spirometry on separate visits)
  • a clinically important increase in lung function (at least 200 mL and 12% from baseline) after ≥ 4 weeks’ treatment trial with an ICS
  • clinically important variation in peak expiratory flow (diurnal variability of more than 10%, calculated over 1–2 weeks as the average of daily amplitude per cent mean)
  • a clinically important reduction in lung function (decrease in FEV1 of at least 200 mL and 12% from baseline on spirometry, or decrease in peak expiratory flow rate by at least 20%) after exercise (formal laboratory-based exercise challenge testing uses different criteria for exercise-induced bronchoconstriction)
  • a clinically important reduction in lung function (15–20%, depending on the test) during a test for airway hyperresponsiveness (exercise challenge test or bronchial provocation test) measured by a respiratory function laboratory.

The greater the variations, or the more occasions excess variation is seen, the more confidently the diagnosis of variable expiratory airflow limitation consistent with asthma can be made.

† Persistent expiratory airflow limitation is indicated by reduced post-bronchodilator FEV1/FVC*

§ Lack of history of atopy does not exclude non-allergic asthma.

‡ Chest X-ray may be normal in a patient with COPD

Adapted from

Global Initiative for Asthma, Global Initiative for Obstructive Lung Disease. Diagnosis and initial treatment of asthma, COPD and asthma-COPD overlap. Updated April 2017. Global Initiative for Asthma and Global Initiative for Obstructive Lung Disease; 2017. Available from: http://ginasthma.org/gina-reports

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Table. Spirometry findings in asthma, COPD and asthma–COPD overlap

Finding

Consistent with

Asthma COPD Asthma–COPD overlap

Normal FEV1 /FVC before of after bronchodilator

  Yes   No   No *

Abnormal lung function

(post-bronchodilator reduced FEV1/FVC and FEV1 < lower limit of normal)

  Yes #   Yes   Yes

Airflow limitation with greater bronchodilator reversibility than in healthy population

(post-bronchodilator FEV1 increase ≥ 12% and 200mL from baseline)

  Yes   Yes   Yes

Marked bronchodilator reversibility

(FEV1 increase ≥ 12% and 400mL from baseline)

  Yes   Possible but unusual   Possible §

FEV1/FVC: ratio of forced expiratory volume in one second (FEV1) to forced vital capacity (FVC), either before or after bronchodilator

* Normal FEV1/FVC is not consistent with COPD unless there is other evidence of chronic non-reversible expiratory airflow limitation.

# This finding is consistent with asthma that is poorly controlled or measured during a flare-up, or can be seen in some patients with longstanding asthma.

‡ The greater the variation, and the more times variation is seen, the more likely the diagnosis of asthma. However, some patients with longstanding asthma may develop persistent airflow limitation.

† Marked reversibility strongly favours asthma and is generally inconsistent with COPD, but does not rule out asthma–COPD overlap.

§ This finding may be seen in patients with asthma–COPD overlap, or occasionally in COPD, especially when FEV1 is low.

Sources

Global Initiative for Asthma, Global Initiative for Obstructive Lung Disease. Diagnosis and initial treatment of asthma, COPD and asthma-COPD overlap. Updated April 2017. Global Initiative for Asthma and Global Initiative for Obstructive Lung Disease; 2017. Available from: http://ginasthma.org/gina-reports

Woodruff P, van den Berge M, Boucher R et al. ATS-NHLBI Asthma COPD Overlap (ACO) Workshop Report. Am J Respir Crit Care Med 2017; 196:375-381. Available from: https://www.ncbi.nlm.nih.gov/pubmed/28636425

 

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Treatment for patients with asthma–COPD overlap

Inhaled corticosteroid treatment at low–moderate doses is essential to reduce the risk of potentially life-threatening flare-ups, even if asthma symptoms appear mild or infrequent.22, 30

Most patients also need treatment with a long-acting bronchodilator (either long-acting beta2 agonist or long-acting muscarinic antagonist) in addition to an inhaled corticosteroid. Long-acting beta2 agonists and long-acting muscarinic antagonists should not be used by people with asthma or asthma–COPD overlap unless they are also taking an inhaled corticosteroid (either in combination or separately).

Table. Long-acting bronchodilators for asthma–COPD overlap

Class

Dosing frequency

Agent

Brand name

ICS–LABA combinations

Once daily

Fluticasone furoate + vilanterol

Breo Ellipta 100/25 microg

  • Do not prescribe 200/25 microg formulation#
Twice daily

Budesonide + formoterol

Symbicort Rapihaler

Symbicort Turbuhaler

Twice daily

Fluticasone propionate + formoterol

Flutiform

Twice daily

Fluticasone propionate + salmeterol

Fluticasone and Salmeterol Cipla

Seretide Accuhaler

Seretide MDI

LABAs*

Once daily

Indacaterol

Onbrez Breezhaler

Twice daily Formoterol

Oxis

Foradile

Twice daily Salmeterol

Serevent Accuhaler

LAMAs* Once daily Glycopyrronium

Seebri Breezhaler

Once daily

Tiotropium

Spiriva

Spiriva Respimat

Once daily

Umeclidinium

Incruse Ellipta

Twice daily Aclidinium

Bretaris Genuair

LABA–LAMA combinations*

Once daily

Indacaterol + glycopyrronium

Ultibro Breezhaler

Once daily

Olodaterol + tiotropium

Spiolto Respimat

Once daily

Vilanterol + umeclidinium

Anoro Ellipta

Twice daily

Formoterol + aclidinium

Brimica Genuair

  • * Ensure that patient is also using regular long-term ICS. LABAs and LAMAs should not be used by people with asthma or asthma–COPD overlap unless they are also taking an ICS, in combination or separately)
  • Advise patients/carers that inhalers should be stored below 30°C and should not be left in cars.

The inhaler must be discarded 1 month after opening the package and removing device from tray. When first opened, patients should write the discard date on the label in the space provided. If stored in the refrigerator, inhaler should be taken out and allowed to return to room temperature for at least an hour before use.

The inhaler must be discarded 6 weeks after opening after opening the package and removing device from tray. When first opened, patients should write the discard date on the label in the space provided. If stored in the refrigerator, inhaler should be taken out and allowed to return to room temperature for at least an hour before use.

# Only the 100/25 microg dose of fluticasone furoate/vilanterol is TGA-approved for treatment of COPD. The higher dose (200/25 microg) is not TGA-approved for the treatment of COPD, so it should not be used in people with asthma–COPD overlap.

High doses of ICS (alone or in combination) are not recommended in patients with COPD and should therefore be used with caution in patients with asthma-COPD overlap, because of the risk of pneumonia.

Refer to PBS status before prescribing.

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Management should also include smoking cessation, treatment of comorbid conditions, physical activity, pulmonary rehabilitation, vaccinations, self-management (including a regularly updated action plan) and regular follow-up.22

Respiratory tract infections should be monitored carefully because people with asthma–COPD overlap have high morbidity rates and because ICS treatment is associated with increased risk of non-fatal pneumonia in people with COPD.31 Most of the available evidence is from patients treated with fluticasone propionate, particularly at higher doses. Increased pneumonia rates have also been observed in studies of patients with COPD using fluticasone furoate/vilanterol. The higher dose of fluticasone furoate/vilanterol (Breo Ellipta 200/25 microg) is not approved for patients with COPD, so it should also not be used in patients with asthma–COPD overlap.

Specialist referral should be considered for patients with atypical symptoms or symptoms that suggest an alternative diagnosis, persistent symptoms or flare-ups despite treatment, or complex comorbidities.

For information on diagnosis and management of COPD, refer to the COPD-X Concise Guide for Primary Care.32

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References

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  30. Adler, A., Uziel, Y., Mei-Zahav, M., Horowitz, I.. Formoterol induces tolerance to the bronchodilating effect of Salbutamol following methacholine-provocation test in asthmatic children. Pulm Pharmacol Ther. 2006; 19: 281-5. Available from: https://www.ncbi.nlm.nih.gov/pubmed/16169761
  31. Pharmaceutical Benefits Scheme,. Post-market review. PBS medicines used to treat asthma in children. Report to PBAC. Final Report. 2017.
  32. Akashi K, Mezawa H, Tabata Y, et al. Optimal step-down approach for pediatric asthma controlled by salmeterol/fluticasone: A randomized, controlled trial (OSCAR study). Allergol Int. 2016; 65: 306-11. Available from: https://www.ncbi.nlm.nih.gov/pubmed/27155753